1. Field of the Invention
The present invention relates to a device for sorting and selectively collecting flat products, such as shipping pouches, printed products or workpieces, which are placed at predetermined collecting points along the conveying path of an endless conveyor and below the conveyor in collecting containers, wherein the empty collecting containers can be moved transversely of the direction of movement of the conveyor on a transfer path between a lateral pick-up position and the collecting point by a pushing device which is reversibly driven in a guide arrangement of the transfer path, and wherein the filled collecting containers can be ejected from the collecting point.
2. Description of the Related Art
A device of the above-described type, as disclosed in EP-A-0 899 026, is used for sorting flat products, such as shipping pouches, printed products or workpieces, which have been individually supplied by conveyors and which are placed on the conveying path in collecting conveyors along the conveying path at several collecting points or filling stations provided underneath the conveyor.
If feeding of the empty collecting conveyors to the pushing device is to take place automatically, for example, as described in European patent application no. 98810308, the drive of the pushing device is to be constructed accordingly.
Therefore, it is the primary object of the present invention to construct the pushing device in such a way that it permits an automatic feeding with empty collecting containers in a simple manner.
In accordance with the present invention, the pushing device is connected for driving the pushing device to a drive member of a fixedly mounted drive unit, wherein the drive member is attached to an endless traction means.
The configuration according to the present invention makes it possible to provide a simple construction of the pushing device which is capable of precisely moving into the required positions, is low in wear and easy to maintain.
In accordance with an advantageous feature of the present invention, the drive member is driven on parallel portions of a travel path of two guide rollers arranged spaced apart in the direction of movement of the pushing device, and the drive member is mounted so as to be movable back and forth transversely of the direction of movement of the pushing device in a hollow space of the pushing device provided with walls which are connected so as to be drivable together. This makes it possible to use simple drive elements.
In accordance with an advantageous feature, the travel path of the drive member is determined by the length of the transfer path which is at least equal to the length of the parallel portions of the travel path.
It is advantageous if the hollow space receiving the drive member has in the transverse direction thereof at least the width of the travel path of the drive member in the area of a guide roller, so that the configuration is low in wear and damps noise.
In accordance with another advantageous feature, the hollow space has two walls located opposite each other and especially resting against the drive member at the parallel portions of the travel path, wherein the drive member moves at the walls in the deflection area of the guide rollers transversely of the direction of movement of the pushing device.
The drive unit is advantageously placed underneath the pushing device, so that a compact construction is achieved and the components thereof are easily accessible.
The pushing device is preferably divided into an area for the collecting container and an area following in the direction of movement and provided for the guiding arrangement or the drive unit, so that a favorable construction and a separation of the individual movement components can be achieved.
In accordance-with an advantageous feature, the collecting container area is arranged as seen in the transfer direction behind the area of the pushing device provided for the guide arrangement or the drive unit, so that an optimum drive concept between the pick-up position and the collecting point can be achieved.
In accordance with a recommended feature, the guide roller of the traction means connected to a motor is arranged between the pick-up position and the collecting point of a collecting container, so that a space-saving but easily accessible arrangement is achieved.
If the pick-up position of the collecting containers is formed by a conveying device for empty collecting containers, it is advantageous if the rearward portion of the pushing device as seen in the transfer direction extends in the initial position into the pick-up position of the collecting containers. If the hollow space constructed as a slot extends perpendicularly of the movement of the pushing device, the speed of the pushing device is increasingly decelerated when the drive member enters the curved path portion formed by the guide roller and is once again increasingly accelerated at the turning point of the curved path portion until the parallel portions of the traction means are reached.
For continuously changing the movement of the pushing device at the deceleration and/or the acceleration end of the transfer path, the guide slot could also be cam-shaped, especially since when filled containers are ejected from the collecting point, a harmful impact of the front edge of the pushing device at the collecting container should be avoided.
If a transversely extending straight guide slot is used, it is because of the running of a motor only possible with appropriate additional technical means (positioning drive or servo drive) to stop the pushing device in a specific position.
As an alternative to the straight or curved guide slot, the hollow space can also be constructed in such a way that for driving the pushing device the drive member is first in contact with a wall arranged transversely of the direction of movement of the pushing device, the drive member then changes its position along the wall and transversely of the direction of movement of the pushing device when traveling around a guide roller, and the drive speed of the pushing device is decelerated in the selected direction at the turning point of the guide roller until zero. From the turning point the wall extends approximately at 90xc2x0 and concentrically relative to the axis of rotation of the guide roller and ends with a portion extending parallel to the direction of movement at the wall which continues transversely of the direction of movement of the pushing device and is constructed as a stop. When the drive member travels around the opposite guide roller, the guide member changes its position at this wall as already-described above.
The hollow space is composed geometrically of two geometric surfaces of equal size which are located diametrically opposite each other at an axis extending transversely of the direction of movement of the pushing device, wherein the geometric surfaces are formed of a square and an adjacent quarter circle and can be compared to an eye which is inclined by about 45xc2x0 and whose pupil is formed by a central guide pin which in the quarter circle area defines together with the wall of the hollow space a guide path.
The drive member fastened to the traction means preferably is composed of a preferably cylindrical drive part protruding into the hollow space and a fastening part connected to the endless traction means, wherein the traction means extends in the axis of the cylindrical drive part, so that a direct drive transmission from the traction means to the pushing device is created.
The drive member is fastened to the traction means by forming a loop of the traction means through which a mandrel extends and which is connected to the fastening part of the drive member, so that the traction means is not weakened.
The loop of the traction means is advantageously anchored in an annular gap formed by the mandrel and above the drive part, so that a reliable drive connection can be achieved.
A support member guided on the transfer path is provided between the drive part and the fastening part, so that a rotation of the traction means between the guide rollers can have no influence on the position of the drive part in the hollow space.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of the disclosure. For a better understanding of the invention, its operating advantages, specific objects attained by its use, reference should be had to the drawing and descriptive matter in which there are illustrated and described preferred embodiments of the invention.